OverviewHave you noticed that the medial arch of your foot is becoming flatter when you walk? You may be developing adult acquired flat foot. This condition is typically caused by a problem with a tendon on the medial side of your foot called the Posterior Tibial Tendon that is not functioning well. You may experience pain in the inner side of your foot when you walk. The affected foot appears to roll outwards (the sole of the foot is trying to face outwards) when you walk. This is called over-pronation of the foot. The back of your heel may start to point outwards (heel valgus). Over time you may lose the ability to tip toe on that foot as the posterior tibial tendon stretches out and it may eventually tear.

CausesOveruse of the posterior tibial tendon is often the cause of PTTD. In fact, the symptoms usually occur after activities that involve the tendon, such as running, walking, hiking, or climbing stairs.

SymptomsThe symptoms of PTTD may include pain, swelling, a flattening of the arch, and an inward rolling of the ankle. As the condition progresses, the symptoms will change. For example, when PTTD initially develops, there is pain on the inside of the foot and ankle (along the course of the tendon). In addition, the area may be red, warm, and swollen. Later, as the arch begins to flatten, there may still be pain on the inside of the foot and ankle. But at this point, the foot and toes begin to turn outward and the ankle rolls inward. As PTTD becomes more advanced, the arch flattens even more and the pain often shifts to the outside of the foot, below the ankle. The tendon has deteriorated considerably and arthritis often develops in the foot. In more severe cases, arthritis may also develop in the ankle.

DiagnosisThe adult acquired flatfoot, secondary to posterior tibial tendon dysfunction, is diagnosed in a number of ways with no single test proven to be totally reliable. The most accurate diagnosis is made by a skilled clinician utilizing observation and hands on evaluation of the foot and ankle. Observation of the foot in a walking examination is most reliable. The affected foot appears more pronated and deformed compared to the unaffected foot. Muscle testing will show a strength deficit. An easy test to perform in the office is the single foot raise. A patient is asked to step with full body weight on the symptomatic foot, keeping the unaffected foot off the ground. The patient is then instructed to "raise up on the tip toes" of the affected foot. If the posterior tibial tendon has been attenuated or ruptured, the patient will be unable to lift the heel off the floor and rise onto the toes. In less severe cases, the patient will be able to rise on the toes, but the heel will not be noted to invert as it normally does when we rise onto the toes. X-rays can be helpful but are not diagnostic of the adult acquired flatfoot. Both feet - the symptomatic and asymptomatic - will demonstrate a flatfoot deformity on x-ray. Careful observation may show a greater severity of deformity on the affected side.

Non surgical TreatmentBecause of the progressive nature of PTTD, early treatment is critical. If treated soon enough, symptoms may resolve without the need for surgery and progression of the condition can be stopped. If left untreated, PTTD may create an extremely flat foot, painful arthritis in the foot and ankle, and will limit your ability to walk, run, and other activities. Your podiatrist may recommend one or more of these non-surgical treatments to manage your PTTD. Orthotic devices or bracing. To give your arch the support it needs, your foot and ankle surgeon may recommend an ankle brace or a custom orthotic device that fits into your shoe to support the arch. Immobilization. A short-leg cast or boot may be worn to immobilize the foot and allow the tendon to heal. Physical therapy. Ultrasound therapy and stretching exercises may help rehabilitate the tendon and muscle following immobilization. Medications. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, help reduce the pain and inflammation. Shoe modifications. Your foot and ankle surgeon may recommend changes in your footwear.

Surgical TreatmentIf conservative treatments don?t work, your doctor may recommend surgery. Several procedures can be used to treat posterior tibial tendon dysfunction; often more than one procedure is performed at the same time. Your doctor will recommend a specific course of treatment based on your individual case. Surgical options include. Tenosynovectomy. In this procedure, the surgeon will clean away (debride) and remove (excise) any inflamed tissue surrounding the tendon. Osteotomy. This procedure changes the alignment of the heel bone (calcaneus). The surgeon may sometimes have to remove a portion of the bone. Tendon transfer: This procedure uses some fibers from another tendon (the flexor digitorum longus, which helps bend the toes) to repair the damaged posterior tibial tendon. Lateral column lengthening, In this procedure, the surgeon places a small wedge-shaped piece of bone into the outside of the calcaneus. This helps realign the bones and recreates the arch. Arthrodesis. This procedure welds (fuses) one or more bones together, eliminating movement in the joint. This stabilizes the hindfoot and prevents the condition from progressing further.